/*******************************************************************************
 * FilePath    : \Software\Examples_Ble\ble_app_peripheral_ota_boot\main.c
 * Version     : 1.0
 * Brief       : 
 * Author      : AndrewHu
 * Company     : Shanghai MacroGiga Electronics CO.,Ltd
 * Email       : Hubinbo@macrogiga.com
 * Date        : 2020-04-03 15:06:14
 * LastEditors : AndrewHu
 * LastEditTime: 2021-04-20 14:49:07
 * Description : 
 ******************************************************************************/
/* Includes ------------------------------------------------------------------*/
#include <Includes.h>
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define APPLICATION_ADDRESS (uint32_t)0x00001010

#define BANK_ID_A (0)
#define BANK_ID_B (1)
/*
0~3KB BootCode
3~4KB UserData
4~34KB RunCode
34~64KB OTA
*/
#define BANK_BASE 0x00000000
#define BANK_A_OFFSET (1024 * 4)
#define BANK_A_SIZE_KB_MAX (30)
#define BANK_B_OFFSET (BANK_A_OFFSET + 1024 * BANK_A_SIZE_KB_MAX)
#define BANK_B_SIZE_KB_MAX (30)
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
//CRC algorithm
static const unsigned short CrcCCITTTable[256] =
    {
        0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7,
        0x8108, 0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF,
        0x1231, 0x0210, 0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6,
        0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE,
        0x2462, 0x3443, 0x0420, 0x1401, 0x64E6, 0x74C7, 0x44A4, 0x5485,
        0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D,
        0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6, 0x5695, 0x46B4,
        0xB75B, 0xA77A, 0x9719, 0x8738, 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC,
        0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823,
        0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969, 0xA90A, 0xB92B,
        0x5AF5, 0x4AD4, 0x7AB7, 0x6A96, 0x1A71, 0x0A50, 0x3A33, 0x2A12,
        0xDBFD, 0xCBDC, 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A,
        0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03, 0x0C60, 0x1C41,
        0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD, 0xAD2A, 0xBD0B, 0x8D68, 0x9D49,
        0x7E97, 0x6EB6, 0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70,
        0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A, 0x9F59, 0x8F78,
        0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C, 0xC12D, 0xF14E, 0xE16F,
        0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067,
        0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C, 0xE37F, 0xF35E,
        0x02B1, 0x1290, 0x22F3, 0x32D2, 0x4235, 0x5214, 0x6277, 0x7256,
        0xB5EA, 0xA5CB, 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D,
        0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
        0xA7DB, 0xB7FA, 0x8799, 0x97B8, 0xE75F, 0xF77E, 0xC71D, 0xD73C,
        0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634,
        0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9, 0xB98A, 0xA9AB,
        0x5844, 0x4865, 0x7806, 0x6827, 0x18C0, 0x08E1, 0x3882, 0x28A3,
        0xCB7D, 0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A,
        0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0, 0x2AB3, 0x3A92,
        0xFD2E, 0xED0F, 0xDD6C, 0xCD4D, 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9,
        0x7C26, 0x6C07, 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1,
        0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA, 0x8FD9, 0x9FF8,
        0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0};
/* Private function ----------------------------------------------------------*/
typedef void (*pFunction)(void);
//#define APPLICATION_ADDRESS (BANK_BASE + BANK_A_OFFSET + 16)  /*first 16 bytes are check data*/
void ClearBank(int BANK_ID_Flag);
/* extern --------------------------------------------------------------------*/
/*******************************************************************************
 * Function    : Error_Handler
 * Brief       : 错误中断
 * Parameter   : 
 * Returns     : 
 * Date        : 2021-04-20 14:48:51
 * Description : 
 ******************************************************************************/
void Error_Handler(void)
{
    /* USER CODE BEGIN Error_Handler_Debug */
    /* User can add his own implementation to report the HAL error return state */

    /* USER CODE END Error_Handler_Debug */
}
/*******************************************************************************
 * Function    : CRC16
 * Brief       : CRC校验函数
 * Parameter   : 
 * Returns     : 
 * Date        : 2021-04-20 14:36:11
 * Description : init CRC with 0x0000
 ******************************************************************************/
unsigned short CRC16(unsigned char *Buf, int BufLen, unsigned short sCRC)
{
    register int i;

    for (i = 0; i < BufLen; i++)
    {
        sCRC = (sCRC << 8) ^ CrcCCITTTable[((sCRC >> 8) ^ *Buf++) & 0x00FF];
    }
    return sCRC;
}
/*******************************************************************************
 * Function    : Jump2App
 * Brief       : 跳转到APP空间
 * Parameter   : 
 * Returns     : 
 * Date        : 2021-04-20 14:34:19
 * Description : 
 ******************************************************************************/
void Jump2App(uint32_t AppAddr)
{
    pFunction Jump_To_Application;
    uint32_t JumpAddress;

    JumpAddress = *(__IO uint32_t *)(AppAddr + 4);
    Jump_To_Application = (pFunction)JumpAddress;

    /* Initialize user application's Stack Pointer */
    __set_MSP(*(__IO uint32_t *)APPLICATION_ADDRESS);

    /* Jump to application */
    Jump_To_Application();
}
/*******************************************************************************
 * Function    : CheckCodeBank
 * Brief       : 校验空间代码
 * Parameter   : 
 * Returns     : 
 * Date        : 2021-04-20 14:37:05
 * Description : 
 ******************************************************************************/
int CheckCodeBank(int BANK_ID_Flag)
{
    uint16_t Size, Crc = 0;
    uint8_t *BankAddr = (uint8_t *)(BANK_BASE + BANK_A_OFFSET); //BANKA

    if (BANK_ID_Flag == BANK_ID_B)
    {
        BankAddr = (uint8_t *)(BANK_BASE + BANK_B_OFFSET);
    }

    //size2B,crc2B LE
    Size = BankAddr[1];
    Size <<= 8;
    Size |= BankAddr[0];
    if (Size > BANK_B_SIZE_KB_MAX * 1024 - 16) //for safe, error found
    {
        Size = BANK_B_SIZE_KB_MAX * 1024 - 16;
    }

    Crc = CRC16(BankAddr + 16, (int)Size, Crc);

    if (((Crc & 0xFF) != BankAddr[2]) || (((Crc >> 8) & 0xFF) != BankAddr[3]))
    {
        ClearBank(BANK_ID_B);
        return 0; //failed
    }

    return 1; //OK
}
/*******************************************************************************
 * Function    : ClearBank
 * Brief       : 清除空间
 * Parameter   : 
 * Returns     : 
 * Date        : 2021-04-20 14:38:01
 * Description : 
 ******************************************************************************/
void ClearBank(int BANK_ID_Flag)
{
    FLASH_EraseInitTypeDef sFlashEraseInit;
    uint32_t uiErrorPage;
    int i, clearflag = 0;
    unsigned char *addr = (unsigned char *)(BANK_BASE + BANK_B_OFFSET);
    uint32_t BankAddr = (BANK_BASE + BANK_B_OFFSET);

    if (BANK_ID_Flag == BANK_ID_A)
    {
        addr = (unsigned char *)(BANK_BASE + BANK_A_OFFSET);
        BankAddr = (BANK_BASE + BANK_A_OFFSET);
    }

    for (i = 0; i < BANK_B_SIZE_KB_MAX * 1024; i++)
    {
        if (0xff != *addr++)
        {
            clearflag = 1;
            break; //not empty
        }
    }

    if (clearflag)
    {
        for (i = 0; i < BANK_B_SIZE_KB_MAX; i++)
        {
            sFlashEraseInit.TypeErase = FLASH_TYPEERASE_PAGES;
            sFlashEraseInit.PageAddress = BankAddr + i * 1024;
            sFlashEraseInit.NbPages = 2;
            if (HAL_FLASH_Erase(&sFlashEraseInit, &uiErrorPage) != HAL_OK)
            {
                Error_Handler();
            }
        }
    }
}
/*******************************************************************************
 * Function    : CopyB2A
 * Brief       : 拷贝空间B代码到空间A
 * Parameter   : 
 * Returns     : 
 * Date        : 2021-04-20 14:38:35
 * Description : 
 ******************************************************************************/
void CopyB2A(void)
{
    uint16_t i, Size;
    uint32_t BankAddrA = BANK_BASE + BANK_A_OFFSET, Data;
    unsigned char *addr = (unsigned char *)(BANK_BASE + BANK_B_OFFSET);

    Size = addr[1];
    Size <<= 8;
    Size |= addr[0];
    Size >>= 2;
    Size += 4; //header 16 bytes

    if (Size > BANK_B_SIZE_KB_MAX * 256) //error
    {
        Size = BANK_B_SIZE_KB_MAX * 256;
    }

    //clear
    ClearBank(BANK_ID_A);

    for (i = 0; i < Size; i++)
    {
        Data = addr[3];
        Data <<= 8;
        Data |= addr[2];
        Data <<= 8;
        Data |= addr[1];
        Data <<= 8;
        Data |= addr[0];

        HAL_FLASH_Program(FLASH_TYPEPROGRAM_WORD, BankAddrA, Data);

        BankAddrA += 4;
        addr += 4;
    }

    //check
    if (!CheckCodeBank(BANK_ID_A)) //Flash error????
    {
        //...
    }
}
/*******************************************************************************
 * Function    : main
 * Brief       : 主函数
 * Parameter   : 
 * Returns     : 
 * Date        : 2020-04-03 17:14:47
 * Description : 
 ******************************************************************************/
int main(void)
{
    //RCC_APB2PeriphClockCmd(RCC_APB2Periph_SYSCFG, ENABLE);

    //check bankB
    if (CheckCodeBank(BANK_ID_B))
    { //校验空间B的代码，如果有代码且校验通过，将B空间的代码拷贝到A空间，然后清除B空间
        CopyB2A();
        ClearBank(BANK_ID_B);
    }

    //跳转到A空间执行
    Jump2App(APPLICATION_ADDRESS);

    /* Infinite loop */
    while (1)
    {
    }
}
